There are 3 titles associated with this firm.

Betham, Mary M. A Biographical Dictionary of the Celebrated Women of every Age and Country. By Matilda Betham. London: Benjamin Crosby and Co., Thomas Tegg and Castleman, Edmund Lloyd [24 Harley Street], 1804.
Bayfield, Mrs. E. G. Fugitive Poems. By Mrs. Bayfield. London: 1805.